14 August 2008

Aside from UTP cable 4 pairs, we also have 25 pairs UTP cables and even more than 2400 pairs of UTP cable.
Usually, the 25 pairs UTP cables are terminated to 110 blocks, 66 blocks, etc using a Punch Down Tool.

There is a wiring scheme that you must follow to terminate the 25 pairs UTP cables.
Here is the wiring scheme color codes:

You can see from table all cable pairs from the pair 1 to pair 25. Here's how to read the table:

In 25 pairs UTP cable, you have 5 group of paired cables. Each group has 5 basic colors, Blue, Orange, Green, Brown, Grey (Slate). Each cable twisted with the same group color (e.g. first group is white, second group is red, and so on).

You can see on the top picture how the 25 pairs UTP cables are terminated according to the color scheme.

Cables that have larger than 25 pairs are group per 25 pairs. The first group should have a binder ribbon with White/Blue color, the second group have a White/Orange binder, and so on.

Unless you're working on a major project, you will see the 25 pairs UTP cables are commonly used in projects.